<ion-header>
  <ion-toolbar>
    <ion-buttons slot="start">
      <ion-back-button defaultHref="/tabs/tab1"></ion-back-button>
    </ion-buttons>
    <ion-title>modal</ion-title>
  </ion-toolbar>
</ion-header>

<ion-content padding>
   <ion-button (click)="showModel()">
     弹出模态对话框
   </ion-button>
</ion-content>
